| Causes of erythema and white spots on the surface of gold products were analyzed and experimentally verified under simulated conditions, and experiments of eliminating erythema and white spots were conducted. The results show that, erythema on the surface of gold products may be formed by impurity oxidation, and can be eliminated by hot dilute hydrochloric acid; white spots could be gold amalgam which can be eliminated after 450oC/30min and 910 oC/10min heat treatment. Both of two methods slightly affects the original surface gloss of gold products, and don’t affect the original color and weight. |
